So I installed the MD ART/Exhaust combo on my 2007 350z HR and I got a dynotune (292 rwhp). The fuel smell is still present, and I wish I knew that removing the cats and installing test pipes would create this fuel smell. I even did a decent amount of reading on the forums and it wasn't brought up. Sigh. This fuel smell (running rich) is also causing the exhaust to making popping noises, which I personally am not the biggest fan of.

So this leads me to my question: How can I get rid of this smell? Do I need another dynotune to raise the Fuel/Air mixture? Would a dyno do anything? Would me trying to run lean do anything?

 

put on cats

btw, if you were tuned, i doubt you are running rich.

 

Would the high flow cats eliminate exhaust fumes in the cabin?

 

I just sold the OEM cats. Also, the MD exhaust plus oem cats made my car REALLY loud. Like even too loud in the cabin with music loud. Funny though

What aftermarket cats would you recommend for my current setup? Would I need a new dyno? Would cats result in HP/torque loss over MD ARTs? Also, I want to get a supercharger installed in the next 6-12 months. Would an SC make the fuel smell better or worse?

K&N Dropfilters
MD ART
MD Exhaust

 

it would have less of smell. motordyne has a hfc module you can get. by going back to cats you will gain some torque and lose a couple horses.. nothing major. could you live without a retune, yeah sure... would you get more of the car and mods to retune it, i would.

when looking at cats, look at the cell count. i had kinetix and they were okay, alot of people like berk

you are smelling pure exhaust right now, the cats remove or convert some of the elements. if you want to know all the specifics this is a pretty good read

http://www.explorecuriocity.org/Cont...contentid=1779

 

I will come pick up your ART pipes if you don't want them. I am local.

 

Looking at the MD site, I see an "XYZ Catalytic Converter" and then a "350Z XYZ pipe with HFC". I don't understand how either would them would fit with the rest of the ART/Exhaust, even if you did remove the ARTs. The attachments are too different (bolts vs clamp)

 

THE XYZ pipe is a Y-pipe connecting the ART pipes and the rest of the exhaust. THE HFC is the piece coming out of the end of Y pipe closer to the rear.

Red arrow points out the straight pipe piece / HFC. Blue arrow points at the XYZ pipe.

 

That picture helps a ton. The problem is that I don't have the straight pipe from HFC to the Muffler. Look at the attachment hardware, is that single pipe, muffler, twin pipes all one piece?

 

I might be misinterpreting what you're saying. But, as far as I know on the MotorDyne exhaust the red arrow is the HFC module, it can also be a cat, or straight pipe depending on which piece you bought. I believe the full exhaust comes with the HFC standard (could be wrong). However, that piece is removable as it is attached using a v-band clamp.

 

I have the TDX2, pictured below. You see how the Y pipe to Muffler is a clamp? Well that HFC piece in your picture is by bolts. It won't attach to my muffler.

 

Because the tdx2 eliminates the module section your choices are to get rid of tdx2 buy xyz pipe with cat module or sell art pipes and get hfc.

 

call or email tony... see what he can do for you

 

yeah, that may be my only option. I actually called him earlier today he said that the smell is def because of no cats. However, he said that exhaust pops shouldnt be there, even with no cats. The pops mean too much fuel is being used/burned, and that happens before the cats, so I'm running rich. I need to call PTunning (Manassass, Va) and have them increase the fuel/air ratio.

I called PT and they said that they could do a dynopull to check the F/A, but they just did a dynotune on it 2 weeks ago. Could it be that they missed something? I get that the smell would exist, but why the pops?

Then I made this thread.

 

when do you the the pops? here is my old car. to me, your car doesn't sound like it was tuned properly

 

I hear the pops when RPMs go down. So this generally happens after I do a big RPM increase like you were doing, and then putting it into a higher gear. Basically alot like yours.

Was yours tuned properly in that clip?

 

I'm still trying to figure out when people would get rid of OEM cats. I can understand if they are bad or the car is a dedicated track car but.......

 

Multiple shops said supercharger gains would be a lot more with ART pipes/HFCs.

looks like dumb me

 

Any time put more air in you want to get it out with as little restriction as possible.

 

right, but i didnt know there would be an accompanying fuel smell + pops. I read that somepeople like the pops -- personally i hate them.

Im going to call Ptuning again tomorrow. Ask them if I am running rich (fuel smell + existence of pops), if we could try to run the car a bit leaner. Hopefully would remove both, and the performance hit can't be more then 1-2%